Preparation of unsaturated oils with a crystalline violet titanium trichloride and ethyl aluminum dihalide catalyst



United States Patent 3,403,197 PREPARATION OF UNSATURATED OILS WITH ACRYSTALLINE VIOLET TITANIUM TRI- CHLORIDE AND ETHYL ALUMINUM DIHA- LIDECATALYST Charles W. Seelbach, Cranford, Erik G. M. Tornqvist, Roselle,and Arthur W. Langer, Jr., Watchung, N.J., assignors to Esso Researchand Engineering Company, a corporation of Delaware No Drawing.Continuation-impart of application Ser. No. 692,050, Oct. 24, 1957. Thisapplication Dec. 1, 1965, Ser. No. 510,956

2 Claims. (Cl. 260683.15)

This application is a continuation-in-part of Ser. No. 692,050, filedOct. 24, 1957, now abandoned.

This invention relates to the low pressure polymerization of alphaolefins to low molecular weight unsaturated oils. More particularly, itrelates to a process of this nature wherein the alpha olefin monomershaving at least three carbon atoms are polymerized with a catalystsystem containing a crystalline, partially reduced, heavy transitionmetal halide.

The low pressure polymerization of alpha olefins with catalyst systemsmade up of reducible, heavy transition metal compounds and a reducing,metal-containing compound to high density, isotactic, high molecularweight, solid, relatively linear products has been assuming everincreasing importance and is now well known, e.g., see Belgian Patent533,362, Chemical and Engineering News, Apr. 8, 1957, pages 12 through16, and Petroleum Refiner, December 1956, pages 191 through 196.

It has now surprisingly been found that alpha olefins can be polymerizedto low molecular weight, highly unsaturated oils by the use of acatalyst system containing as one component a crystalline, partiallyreduced, heavy transition metal halide. In the present system, acomplete active catalyst for promoting the formation of unsaturatedpolyolefin oils is formed by adding to the heavy transition metal halidean aluminum compound having the formula AlR X wherein m is a cardinalnumber from 0 to 1, n is an integer from 2 to 3, m.+m totaling 3, R is aradical selected from the group consisting of alkyl and aryl radicals,said radicals preferably having from 1 to 6 carbon atoms, and X is achlorine or bromine atom.

Although AlR X activators when used in conjunction with partiallyreduced, transition metal halides are undesirable because they serve toproduce high molecular weight, solid polymers, amounts up to about 25wt. percent of AlRX in the preferred activator system can be toleratedas the resulting catalyst still produces predominantly oily, liquidpolymers. Presumably, this is due to the fact that AIR- X activatorscomplex very strongly with transition metal halide surfaces and largelyexcludes the AlR X activators from the active catalyst sites. The molarratio of aluminum compound to transition metal compound in the catalystsystem may vary from 1:4 to 50:1, preferably 2:1 to less than :1.

The alpha olefin feed utilized in the polymerization may have from 3 to40, preferably 3 to 20, carbon atoms and thus includes propylene,butene-l, pentened, heptenel, dodecene-l, tetradecene-l, etc.

Temperatures utilized in the preparation of the oily polymers may varyfrom about 0 to 250 C., preferably 30 to 200 C. although temperatureslower than 0 C. may also be advantageously employed, especially whenlower molecular weight olefins such as propylene and butene-l arepolymerized. The pressures at which the reaction is conducted could varyin the range of about 0 to 1000 p.s.i.g., preferably 10 to 500 p.s.i.g.,depending primarily upon the volatility of the olefin monomer andreaction diluent and upon the reaction temperatures used.

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The principal component of the catalyst system utilized are crystalline,partially reduced, heavy transition metal halides. The metals exhibitinga catalytic activity are the transition metals of the IV, V, VI and VIIIgroups of the Periodic System, e.g., titanium, zirconium, hafnium,thorium, vanadium, niobium, tantalum, chromium, molybdenum and tungstenas well as iron, cobalt and nickel. The chlorides and bromides of theabove-named metals are generally preferred; titanium, vanadium andzirconium chlorides, and bromides being the most active. Titaniumtetrachloride, titanium tetrabromide, vanadium tetrachloride, zirconiumtetrachloride, and zirconium tetrabromide may be readily reduced to thedesired catalyst component at low activation temperatures.

Crystalline, violet TiCl is particularly preferred as a crystallinereduced catalyst component. This material can be prepared in a number ofways:

(1) Reduction of T iCl.,

(a) by metals, i.e., Ti, Zr, Sb, Na, Al, etc., alone or catalyzed byvarious metal halides,

(b) by hydrogen,

(c) thermally at 6001200 C.

(2) Reduction of TiCl, to brown amorphous solids which are converted topurple or violet crystalline TiCl by heating above 150 to 200 C. Theamorphous solids are prepared by (a) metal alkyl reduction of TiCl, atmoderate temperatures, e.g., below about C.,

(b) hydrogen reduction initiated by silent electric discharges attemperatures below about 100 C.

The methods of preparation of these reduced heavy metal compounds areelaborated upon in US. Patent No. 3,128,252, issued Apr. 7, 1964.

The temperatures of reduction will vary with each particular combinationof compounds used, but as a rule the most suitable temperatures arebetween about and 600 C., except for straight thermal reduction(decomposition), and in most cases between 250 and 500 C. Naturallythere is a minimum temperature that can be employed in each case,although quite often a somewhat higher temperature may give a moredesirable product. The optimum reduction temperature will of course bebelow that at which over reduction or decomposition of the desiredreduced transition metal compound takes place. The pressure may be from1 to 50 atmospheres, preferably from 2 to 30 atmospheres, and the timemay vary from a few minutes to 100 hours, or more, generally about 1 to30 hours, depending of course upon the temperature and the types,proportions and amounts of materials used.

While the reduced metal halide, e.g., TiCl itself may exhibit somecatalyst activity, the latter is greatly enhanced by the addition of analuminum compound having the formula presented previously. Theselectivity of the type of aluminum compounds employed should be notedin that when one atom of halogen or less are attached to the aluminumatom, e.g., triethyl aluminum, a solid product is formed rather than thedesired liquid. Typical utilizable compounds are Al(CH )Cl Al(C H )ClAlCl Al (CH Br etc.

When the activating compound for the crystalline partially reducedtransition metal halide is a trihalide, e.g., AlCl it can be formed insitu during the Ti reduction procedure. In this case part of thereduction may be carried out by the transition metal itself. A solublesalt or salt mixture is then formed during the reaction. Depending uponthe proportions and type of starting materials used, the soluble saltwill either cocrystallize or intimately mix with the reduced transitionmetal compound. The following equations will illustrate this type ofprocedure.

The amount of catalyst used may vary within wide limits dependingsomewhat on the purity of the olefin feed. Proportions of as little as0.1 part by weight of catalyst per 100 parts by weight of olefin aresufiicient if the feed is pure. With olefin feed streams containingabout 0.01% of water, oxygen, carbon dioxide or certain other oxygenatedcompounds, catalyst proportions of about 01-10 g. per liter of reactionmixture are usually adequate.

The preparation of the activated catalyst may be carried out in anydesired manner, e.g., by adding a solution of Al(C H )Cl dissolved in asuitable inert, organic solvent to a suspension of the reducedtransition metal halide catalyst constituent at a suitable temperatureranging from 0 to 100 C. but preferably about to C., preferably withagitation to maintain the activated catalyst as a fine solid dispersionin the inert diluent.

The resulting activated dispersed catalyst is then ready for use inpolymerizing propylene or other suitable olefins. This is preferablycarried out by adding the olefin, in either gaseous or liquid state,directly to the reactor containing the dispersed catalyst in thediluent, preferably with constant agitation.

Paraffinic hydrocarbons such as isopentane, heptane, decane or othersaturated petroleum or synthetic hydrocarbon oils, e.g., white mineraloil, naphthenes such as methylcyclohexane or Decalin, aromatics such asbenzene, chlorobenzene, xylene, etc., are the most suitable diluents. Itis important that a suitably high boiling diluent or a high enoughpressure be chosen to maintain the diluent in liquid form at thetemperature employed.

The unsaturated oil products are worked up by quenching the catalystwith alcohol, dilute acid, water, a chelating agent, and similarmaterials and then washing out the residue. The oil is isolated bydistilling off the reaction diluent.

This invention and its advantages will be better understood by referenceto the following examples.

isolated as a brown oil (3.3 grams) with a molecular weight of 375 bycryoscopic procedure.

This example shows how the reduced TiCl without any aluminum alkylcompound, operates itself as a catalyst, but only small product yieldsare obtained.

Example 3 Using the same technique as for Example 2 and the TiClprepared as in Example 1, 18.6 grams of oil was obtained which had amolecular weight, cryoscopic, of 349 and an unsaturation value of 105cg. I/gram of polymer oil.

This example demonstrates that the TiCl containing cocrystallized AlClis an effective catalyst and gives improved results over TiCl alone.

Example 4 One-half gram of TiCl (Ti metal reduction), 425 ml. ofn-heptane and 3.8 ml. of 0.225 gram/ml. solution of ethylaluminumsesquichloride were added to a one liter Cr-V steel bomb. The aluminumsesquichloride contained 86% AlEtCl and a minor amount of AlEt Cl. Coldliquid propylene (100 grams) was injected and the bomb heated to 84 C.for 20 hours. The resulting light brown oil weighed 67 grams for anoverall catalyst efliciency of gram/gram, had a cryoscopic molecularweight of 280 and an unsaturation value of 65.4 (cg. I/gram of polymeroil).

This example shows how improved results are obtained by using theactivator compounds of this invention.

Example 5 A similar experiment to Example 4 omitting the TiCl resultedin no liquid polymer.

This example demonstrates that the aluminum alkyl compound itself had nocatalytic activity.

Example 6 A feed of 100 grams of propylene and 21 grams of heptane wascharged to a bomb and polymerization conducted at C. with a catalystconsisting of CH AlCl and TiCl the Al/Ti ratio being 3. A yield of 21.7grams of oil product was obtained, indicating a catalyst efficiency ingram/gram of 11.

The features of these examples are further summarized in the followingtable.

TABLE I.POLYPROPYLENE OILS Polymerization:

atalyst TiCl; TiCl TiCl; 0.86 AlEtCl; A101; (0.86 AlEtClz 0.14 AlEtzCl0.14 AlEtzCl) Cat. E11, g./g 3 5O Polymer Properties:

Mol. Wt. cryoscopic 375 349 280 Unsat. Value, cg. I/gram of polymer 10565. 4

Example l.-TiCl reduction by Ti+Al 142.3 grams mole) TiCl 3.98 gramsatom) Ti and 4.49 grams GA; atom) Al were charged into a dry 300 ml.steel bomb. The bomb was placed on a heating rocker and heated to 435 C.for 25 hours. After cooling down and opening the bomb, an almostquantitative yield of a violet-purple homogeneous mixture of TiClcocrystallized with AlCl in the mole ratio 5/1 was obtained. The productwas microcrystalline and more easily powderized than the TiCl preparedby reducing TiCL, with Ti in a similar fashion.

Example 2 One grams of TiCl prepared by Ti reduction of TiCL; and 70 ml.of n-heptane were placed in a 300 ml. Cr-V steel microbomb. Cold liquidpropylene (50 grams) was injected and the bomb heated to 200 C. for 20hours. The reaction mixture was placed in ml. of isopropanol and themixture evaporated to dryness. The polymer was Pretreated catalystsystems, i.e., unreduced, heavy, transition metal halides which aretreated with metal alkyls prior to contact with olefins also have someutility, e.g., TiCl +MeAlCl or TiCLfi-(C HQAICI Example 7 of certaincatalysts in promoting the formation of polymer oils from butene-l,pentene-l, hexene-l, octene-l, and decene-l.

Each of the polymerization runs was conducted in a 283 milliliterchrome-vanadium steel bomb. According to the preferred polymerizationprocedure, the desired amount of diluent was first charged to acarefully dried 6 sure nitrogen through the intermediate bomb which wasinterconnected with the polymerization reactor.

In the case of both propylene and higher alpha olefins, thepolymerization reaction was commenced by heating steel bomb locatedinside a dry box containing essentially 5 the bomb to the polymerizationtemperature. At the comoxygen and moisture-free nitrogen. The transitionmetal pletion of the polymerization test, the bomb was rehalide was thenintroduced into the bomb followed by the moved from the rocker andopened and its contents metal alkyl activator. The metal alkyl catalystactivator poured into about 500 milliliters of dry isopropanol. On wasusually added as a 1 molar solution in the diluent occasion, some solidor higher molecular weight liquid chosen for the experiment. Followingcatalyst introduc- 1O polymer precipitated from the polymer solutionupon tion, the desired amount of carefully dried monomer was contactwith the alcohol. When this occurred, the polyinjected into the bomb. Inthe case of butene-l and mer was removed by filtration and the remainingliquid higher alpha olefins the monomer was added in liquid mixtureevaporated on a steam bath. After this operation, form directly in thedry box whereupon the bomb was a mixture of polyolefin oil and catalystresidues was seclosed and transferred toarocker. cured from which theoil could be extracted with n- In the case of propylene, the bomb wasfirst closed and heptane. Minor amounts of catalyst residues whichdistransferred to a heating rocker and then connected to a solved in then-heptane solution were then removed by propylene feed system. Thedesired amount of propylene water extraction. The pure essentiallycolorless polywas condensed in an intermediate bomb positoned in aolefin oil was recovered from the organic solution by Dry Iceisopropanol bath. Prior to use, the propylene evaporating then-hep'tane. was purified by passing it through a barium oxide tower Thepolymer oils thus obtained were then submitted and a scrubber containinga triethyl aluminumfor analysis to determine cryoscopic molecular weightparaffin oil mixture. The condensed propylene was transand iodine number(cg. I/gram of polymer oil). The ferred to the polymerization reactor bypassing high presresults of the tests are set forth in Tables II-IVbelow.

TABLE II Test 1 2 a 4 s 6 Catalyst:

Transition Metal Halide:

Composition Beta-TiCl; Beta-TiBr; Beta-'IiBra VBra VBr; c vcitaaanicnfiWeight, g .3 0. 0.72 0.73 0.365 0.5. Alkyl Aluminum Halid CompositionAlEtClz AlEtCl2 AlEtClz Weight, g Al/Transition Metal Molar ReactionConditions:

Propylene, g Diluent:

Type Volume, ml Temperature, C Time, hrs Results:

Solid or High Mol.- Wt. Liquid 0 0.1

Polymer,

g. Liquid Polymer, g 0.8 3.7 2.2 12.6 2.0 4.4.

Properties of Oily Polym er: Molecular Weight (Cryoscopic) 613 588 421Iodine Number 42.8

gPrepar-ed by gamma radiation induced reduction of TiCh in neptane.

b Prepared by reduction of TiBn with activated aluminum powder inbenzene slurry at C. AlBls formed in the reaction is hydrocarbon solubleand is essentially removed by washing. Preparation steel ball milled 6days. I

0 Prepared by halogen exchange between HBr and VCl in liquid AlBra at240 C. Preparation steel ball milled 3 days.

d Prepared by reduction of V014 with the stoichiornetrlc amount ofaluminum powder at 240 C. in a steel bomb according to the methoddisclosed in U.S. Patent 3,128,252.

8 Extremely tacky semi-solid low mol. wt. material.

f Largely amorphous material.

TABLE III Test 7 8 9 10 ll Monomer Type Butane-1 Butene-l Butene-lPentene-l Pentene-l. Catalyst:

Transition Metal Halide:

Composition Beta-Tick b VBIs Alpha-TiCla Alpha-T101 ight, g 0.309 0.730.77 0.309. Alkyl Aluminum Halid Composition..- AlEtClz.

eight, g 0.254. Al/Transition meta Reaction Conditions Results:

Solid or High Mol. Wt. Liquid Polymer, g. 2.3 11 0 4 3 d 2.1 d 0 6 dLiquid Polymer, g 3.6 0.4 13 4 9.7 2 0 Properties of Oily Polymer: I

Molecular Weight (Cryoscopie) 661 373 527 446 Iodine Number e Preparedby hydrogen reduction of TiCh at about 1,Q00 C. PreparatIion steel ballmilled 6 days. Hence, may also be considered as deltab See Table II,Footnote (a). a See Table II, Footnote (c). Low Mol. wt. polymer.

TABLE IV Test 12 Monomer Type Hexcne-l Octene-l Octene-l Decene1.

atalyst' Transition Metal Halide: Composition 1 Weight, g

Alkyl Aluminum Ha AlEtOlg Weight, g 0.254

ill/Transition Metal Ratio 1 Reaction Conditions:

Alpha-T101 Alpha-TiClt Beta-T1013 Alpha-Tick."

. AlEtCla. 1.91.

Monomer, g 50 50 50 50.

D iluent Temperature, C

Time, hrs Results:

Solid or High Mol. Wt. Liquid Polymer, g 0 Liquid Polymer, g 3.6Properties of Oily Polymer:

Molecular Weight (Cryoscopic).. 551".-.

Iodine Number 50.0 H: 33.5

3 Prepared by hydrogen reduction 01 TiCli at about 1,000 C. See TableII, Footnote (a).

0 See Table III, Footnote (a).

d Semi-solid material.

The data presented in the three tables above clearly demonstrate thenature and scope of the instant invention in that polymeric oils wereformed from a wide variety of alpha olefins using catalyst systems madeup of transition metal compounds of differing crystalline form incombination with a monoalkyl aluminum dihalide compound.

The advantages of this invention will be apparent to those skilled inthe art. Novel polymer oils of valuable properties are obtained.

The oils of this invention have at least one double bond per moleculeand exhibit cryoscopic molecular weights varying from 150 to 1500,preferably 200 to 1000. The oils are useful synthetic intermediates inthe preparation of detergents, lube oil additives, V.I. improvers,flotation agents, parasitical and agricultural oils, plasticizers, etc.Oils formed by 1,2-addition from C to C alpha olefins that have iodinenumbers between about to 80 are particularly desirable products.

It is to be understood that this invention is not limited to thespecific examples which have been offered merely as illustrations andthat modifications may be made Without departing from the spirit of theinvention. For example, the mol. wt. of the polymer oils obtained may bechanged by the addition of various mol. wt. influencing agents such ashydrogen, and the catalytic properties of the catalyst modified by theaddition of known catalyst modifiers such as alcohols, amines,phosphorics, ethers, esters of organic and inorganic acids, amides, andother compounds exhibiting considerable polarity and/or Lewis basecharacter.

What is claimed is:

1. A process for preparing low molecular weight, highly unsaturated oilscomprising polymerizing an olefin having 3 to 20 carbon atoms underpolymerizing conditions at a temperature in the range of 30 to 200 C. ina hydrocarbon diluent and a pressure in the range from 10 to 500p.s.i.g. with a catalyst system comprising a crystalline violet titaniumtrichloride catalyst activated with a monoalkyl aluminum dihalidewherein the molar ratio of said monoalkyl aluminum dihalide to thetitanium trichloride in the catalyst system in less than 5:1 andrecovering as the predominant product oily, liquid polymers of saidolefin having a cryoscopic molecular weight varying from 150 to 1500 andan iodine number of from 30 to centigrams I/ gram of polymer oil.

2. A process for preparing low molecular weight, highly unsaturated oilscomprising polymerizing an alpha olefin having from 3 to 20 carbon atomsin a hydrocarbon diluent at a temperature of 30 to 200 C. and a pressurefrom about 10 to 500 p.s.i.g. with a catalyst comprising a crystallineviolet, titanium trichloride activated with ethyl aluminum dichloride,the molar ratio of ethyl aluminum dichloride to titanium trichloridevarying from 2:1 to less than 5:1 and recovering as the predominantproduct oily, liquid polymers of said alpha olefin having a cryoscopicmolecular weight varying from to 1500 and an iodine number of from 13 to80 centigrams I/ gram of polymer oil.

References Cited UNITED STATES PATENTS 2,168,271 1/1939 Perquin et al.260-68315 X 2,970,133 l/1961 Sistrunk 260683.l5 X 3,116,274 12/1963Boehm et al. 260683.l5 X 3,118,865 1/1964 Bruce et al. 260683.l5 X3,153,634 10/1964 Thomas 260683.15 X 3,251,901 5/1966 Bacskai260'-683.15

DELBERT E. GANTZ, Primary Examiner.

PAUL M. COUGHLAN, JR., Examiner.

G. CRASANAKIS, Assistant Examiner.

1. A PROCESS FOR PREPARING LOW MOLECULAR WEIGHT, HIGHLY UNSATURATED OILSCOMPRISING POLYMERIZING AN OLEFIN HAVING 3 TO 20 CARBON ATOMS UNDERPOLYMERIZING CONDITIONS AT A TEMPERATURE IN THE RANGE OF 30 TO 200*C. INA HYDROCARBON DILUENT AND A PRESSURE IN THE RANGE FROM 10 TO 500P.S.I.G. WITH A CATALYST SYSTEM COMPRISING A CRYSTALLINE VIOLET TITANIUMTRICHLORIDE CATALYST ACTIVATED WITH A MONOALKYL ALUMINUM DIHALIDEWHEREIN THE MOLAR RATIO OF SAID MONOALKYL ALUMINUM DIHALIDE TO THETITANIUM TRICHLORIDE IN THE CATALYST SYSTEM IN LESS THAN 5:1 ANDRECOVERING AS THE PREDOMINANT PRODUCT OILY, LIQUID POLYMERS OF SAIDOLEFIN HAVING A CRYOSOPIC MOLECULAR WEIGHT VARYING FROM 150 TO 1500 ANDAN IODINE NUMBER OF FROM 30 TO 80 CENTIGRAMS I/GRAM OF POLYMER OIL.